A GPRS (general packet radio service) always-on wireless device typically has a single external connection and maintains a single PDP (packet data protocol) context. An always-on device does everything that it can to keep its connection up all the time, at least while it is instructed to do so. An example of a method of keeping a PDP context up all the time is taught in commonly assigned co-pending U.S. application Ser. No. 10/987,658 entitled “Data-Capable Network Prioritization with Reject Code Handling”. That application is hereby incorporated by reference in its entirety.
For an always-on device that only has a single PDP context and a single application, maintaining the PDP context alone is sufficient to maintain data connectivity for the always-on device. Thus, when the PDP context fails, mechanisms such as those taught in the above-referenced patent application can be implemented to re-establish the PDP context and thereby re-establish the data connectivity with the single application. As abstract example of this is shown in FIG. 1 where there is shown a GPRS always-on device 10 having a single PDP context 12 that maps one-to-one to the device and single application. As such, so long as the device is able to maintain the PDP context, data connectivity to the device is continuous.
Typically data applications are not always-on. For example, some e-mail applications are only activated upon user command. Once activated, the application causes a PDP context to be created, opens a socket and maps the socket to the PDP context. The work concerning the e-mail is completed and then the PDP context and socket are closed. Similar behaviour is implemented to open a socket when web browsing is conducted using a wireless device. Typically, a timer is started after the last user action. When the timer expires (or the application is closed), the PDP context and socket are closed.